This invention relates generally to a shut-off valve for use with pneumatic tools and the like. More particularly, but not by way of limitation, this invention relates to an improved shut-off valve for pneumatic tools and the like that moves rapidly from the open position to the closed position.
Some of the pneumatic tools used in production, such as nut runners and the like, are at least partially computer controlled. Such controls are desirable so that the product being assembled will be uniform in that, for example, equal torque will be imposed on each screw or nut inserted in a particular position. Such controls also increase production rates and quality and decrease the rejection rate of the products.
Accordingly, it has become highly desirable to provide some means of stopping the operation of pneumatic tools as close to instantaneously as possible to take advantage of the computer controls. Efforts in this direction have included the use of solenoid actuated valves in tools manufactured by several companies. In those tools, the solenoid is utilized to either open or close the valve with a spring being provided for the purpose of returning the valve to its original position. The valves have operated satisfactorily, but a faster response time is highly desirable. Accordingly, an object of this invention is to provide an improved shut-off valve for pneumatic tools and the like which is relatively simple to manufacture and easy to maintain and that has an extremely fast response time.